Goodrive600 series high-performance multifunction VFD
Communication networking
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6.4.7 NMT node guarding
By using the node protection service, the NMT master node can detect the current state of each node.
Command
Request: Master node (remote frame)
→ Slave node
COB-ID
No data
0x700 + Node-ID
Response: Slave node
→ Master node
COB-ID
Byte0 (status value)
0x700 + Node-ID
Bit7: Triggering bit; Bits 0 to 6: Status
Description
The most significant bit (MSB) bit 7 of Byte0 (status value) in the response command is the triggering bit, that is, the
value of bit 7 is alternated between 0 and 1 each time when the slave node transmits a response frame to distinguish
frames. Bits 0 to 6 indicate the status of the slave node. Table 6-8 describes the state values and their corresponding
state.
Table 6-8 Status values and their corresponding status
Status value (Byte0: Bit0
–Bit6)
Status
0x00
Initializing
0x04
Stopped
0x05
Operational
0x7F
Pre-operational
Example
For example, the command for the master node to detect the status of slave node 3 is as follows.
Master node (remote frame)
→ Slave node:
COB-ID
No data
0x703
After receiving the node protection command transmitted from the master node, the slave node transmits the following
command response to the master node.
COB-ID
Byte0 (status value)
0x703
0x85
In the command, bit 7 of Byte0 is 1, and the status value is 0×05, indicating that slave node 3 is in the operation status. If
receiving another node protection command, the slave node transmits a command frame in which the status value is
0×05 to the master node, and the value of bit 7 is changed to 0.
6.4.8 Heartbeat packet (Heartbeat Producer)
In some cases, the master node requires that a slave node automatically transmits a frame of heartbeat packets at an
interval, so that it can learn the status of the slave node in real time. The interval parameter (data length: 16 bits; unit: ms)
is defined in the object dictionary 0x1017. A CANopen slave node produces heartbeat packets at the interval of 500ms
by default.
Command
Slave node
→ Master node
COB-ID
Byte0
0x700 + Node-ID
Status value
Description